1. Field of the Invention
This invention relates generally to safety closures, and more specifically to an improved safety closure for a container, vial, or the like and method for opening the closure that is very difficult or virtually impossible for a child to practice.
2. Description of the Prior Art
The great advances made in the field of medicine have been accompanied by a tremendous growth in the variety and types of drugs or medicines available to and stocked by members of the public. Many of these drugs, which are normally dispensed in small capped bottles, are beneficial when taken in the proper recommended dosage, but may be exceedingly dangerous if consumed in quantities that are too large. The simple aspirin tablet, which may be helpful for alleviating headaches, is a good example of such a drug. Also, medicinal liquids are available on the market that may be safe if applied to various parts of the human body, but may be exceedingly dangerous or poisonous if taken internally. The availability of the aforementioned medicinal drugs to small children, who are unaware of the potential danger of these drugs, presents a hazard and threat to their lives. In this day and age, young children are more exposed to such potentially dangerous drugs than at any other time in history. Since the cap normally used on containers for drugs is of the common threaded, screw-on type, it is not difficult for most young children to be able to open these containers and to partake of the contents thereof. It is virtually impossible for adults to sufficiently tighten such caps so that they cannot be removed by a child. Applicant's invention is believed to eliminate the aforementioned potential danger to children by providing a safety closure for a container which an adult may readily open or close, but once closed may not be readily opened by a child.
Safety closures for containers are well known in the art and of varied design ranging from the type in which a cap must be depressed downwardly and removed, or downwardly and turned, to the type in which the cap is removed by thumb pressure exerted upwardly on the cap or by a pull tab integral with the cap. One safety closure comprises an injection molded polypropylene cap with lugs that mesh with notches in the container. The cap is removed by pressing downwardly, preferably with the palm of a hand and simultaneously turning the cap to disengage the lugs from the notches. Other two-piece safety closures are known having a ring rotatably mounted on a container for receiving a cap. The cap is turned or rotated in a cap-tightening direction to a fully tightened position in which rotation of the cap in a cap removing direction merely causes the cap and ring member to rotate together around the rim of the container. The cap is removed by manually arresting the ring and then turning the cap in a cap removing direction. Safety closures of this general type are disclosed in U.S. Pat. Nos. 3,403,803 and 3,486,654.
Another type of safety closure is known of which U.S. Pat. No. 3,850,326 is exemplary comprising a closure having a snap-on lid adapted to open and close the opening and retained in its closed position to give the appearance of the top of the closure. The closure has a portion on its outer surface which is displaceable inwardly to allow a finger of the user to remove the snap-on lid. The displaceable portion is not readily distinguishable from the remainder of the closure.
Although these prior known safety closures operate satisfactorily, many of them are not air and liquid tight which is a desirable feature. In addition, most of them comprise two or more molded parts which have to be assembled resulting in closures that are expensive to manufacture and of questionable reliability. In addition, although most of the safety closures provide a challenge to a child they can be opened since they generally rely on pressure applied at one point, or turning, or a lifting action which are natural actions for a child.